Mingler for temperature conditioning sugar masses



Sept. 13, 1966 R. J. HUSER 3,272,649

MINGLER FOR TEMPERATURE CONDITIONING SUGAR MASSES Filed May 25, 1964 2Sheets-Sheet 1 HHHHHIW INVENTOR. RICHARD J.HUSER A TORNEY Se t. 13, 1966R. J. HUSER 9 2 MINGLER FOR TEMPERATURE CONDITIONING SUGAR MASSES 2Sheets-Sheet 2 MIHMH iled May 25, 1964 INVENTOR.

R l C H A R D J H U 5 ER A T 0 RN EY United States Patent 3,272,649MINGLER FOR TEMPERATURE CONDITIONING SUGAR MASSES Richard J. Huser,Mount Healthy, Ohio, assignor to The Western States Machine Company,Hamilton, Qhio, a

corporation of Utah Filed May 25, 1964, Ser. No. 369,705 8 Claims. (Cl.12717) This invention relates to an improved mingler for temperatureconditioning massecuites, magmas and the like.

In the manufacture or refining of sugar, heat is supplied to themassecuite or magma as the material is held in a tank in readiness fordelivery into centrifugal machines. Such heating is intended to decreaseand hold uniform the viscosity of the material delivered, eithercontinuously or as successive charges, to the centrifugals. Thistemperature conditioning of the massecuite or magma has been heretoforeaccomplished by minglers, for example, of the type disclosed in US.Letters Patent No. 2,654,364, to Joseph Hertrich, in which themassecuite, magma or like material is received in an elongated tankhaving a hollow rotatable shaft extending longitudinally through thelower portion of the tank, and a helical heat transferring-stirrer coilsurrounds the shaft within the tank and is connected with the shaft forrotation of the coil with the shaft and for a circulating flow of hotwater or other heat transferring fluid through the coil by way of thehollow shaft. The turns of the helical coil are spaced radially from thesurface of the hollow shaft so as to permit heat transfer to thematerial at the entire surface of the coil and also at the surface ofthe shaft, and further to cause the helical coil to exert a stirring andconveying action on the material in an effort to obtain uniform heatingof the material in the mingler tank before such material is passed toone or more centrifugal machines through corresponding outlets at thebottom of the tank.

It has been found that, with the known minglers, as described above, themassecuites or other material may be moved longitudinally through thespace between the coil and the shaft as a more or less solid core andthus reach an outlet of the mingler tank for discharge to a centrifugalmachine without being subjected to heat transfer and stirring by thecoil. Thus, the'efficiency of heat transfer from the hot water or otherfluid heating medium to the massecuites or magmas is reduced and uniformtemperature control cannot be accurately maintained. The foregoingdisadvantages of the existing minglers are particularly apparent whenthe mingler is associated with modern, high capacity centrifugalmachines, such as, continuous centrifugals or batch machines havingbaskets of forty-eight inch or larger diameter, in which case the sizeof the mingler tank is increased and the time available for heating themassecuites or magmas is reduced.

Accordingly, it is an object of this invention to provide a mingleraffording better heat transfer to the material in the tank and moreuniform temperature control.

Another object is to provide a mingler for conditioning massecuites,magmas or like material prior to passing the same to centrifugalmachines of high capacity, and wherein the material can be uniformlyraised to the desired temperature without employing a coil temperaturethat is too much higher than the saturation temperature of themassecuites or magmas.

In accordance with an aspect of this invention, a mingler has impellermeans, preferably in the form of paddle-like blades, welded or otherwisesecured to the hollow shaft and extending into the space between thelatter and the turns of the heat transferring-stiffer coil, suchimpeller means being operative, upon rotation of the shaft, to urge thematerial within the space between the coil and the shaft in thelongitudinal direction opposed to the movement of the material by thecoil and also radially outward toward the coil, thereby ensuring thatall material in the tank is uniformly subjected to the action of thecoil before being passed from the mingler to centrifugal machines.

In accordance with another aspect of this invention, the mingler tankhas a compartment therein for each centrifugal machine to which thetemperature conditioned material is to be fed, each compartment havingan inlet and an outlet for the material spaced apart in the longitudinaldirection, and the heat transferring-stirrer coil is arranged to inducelongitudinal movement of the material in the direction from the inlettowards the outlet of the associated compartment, while the bladesconstituting the impeller means on the hollow shaft are arranged tocause longitudinal movement in the opposite direction.

The foregoing, and other objects, features and advantages of thisinvention, will become apparent from the following detailed descriptionof an illustrative embodiment which is to be read in connection with theaccompanying drawings forming a part hereof, and wherein:

FIG. 1 is a side elevational view of a mingler embodying this invention,with the side of the tank thereof being partly broken away to expose theinterior construction;

FIG. 2 is an end elevational view of the mingler;

FIG. 3 is a fragmentary top plan view of the mingler;

FIG. 4 is an enlarged sectional view taken along the line 4-4 on FIG. 1;

FIG. 5 is a fragmentary sectional view taken along the line 5-5 on FIG.4; and

FIG. 6 is a fragmentary sectional view showing the arrangement at oneend of the rotary mingler coil unit.

Referring to the drawings in detail and initially to FIG. 1 thereof, itwill be seen that a mingler or apparatus for temperature conditioningmassecuites, magmas or like material in accordance with this inventionis there generally identified by the reference numeral 10 and includes atank 11 and a rotary mingler coil unit 12 mounted in the tank.

The tank 11 is elongated and preferably of U-shaped cross-section, asshown on FIGS. 2 and 4. The interior of tank 11, particularly in thelower portion thereof, is divided into a number of compartments 13a,13b, 13c and 13 d by means of vertical partitions 14 and 15 extendingacross the tank. The top of each compartment 13a- 13d is defined by alaterally extending plate or partition 16 which is spaced downwardlyfrom the top of the tank and preferably inclined downwardly toward oneside of the tank. The top plates or partitions 16 are preferablyhingedly connected, as at 17 (FIGS. 3 and 4) to the side of the tank 11so that they can be swung upwardly from their normal positions, wherethey rest on flanges 18 carried by the partitions 14 and 15 and endwalls of the tank (FIGS. 1 and 4), so as to afford access to thecompartments 13a-13d.

As shown on FIG. 1, the vertical partitions 14 disposed betweencompartments 13a, 13b and 130, in which the same material is to bemingled or temperature conditioned, extend only up to the level of topplates 16 so that the upper portion of tank 11 above compartments 13a,13b and forms a common supply chamber 19 for such compartments. On theother hand, the partition 15 dividing compartments 13c and 13d, whichare intended to handle different materials, extends above plates 16 upto the top of tank 11 so that the top portion of the tank abovecompartment 13d defines a supply chamber 20 which is isolated from thepreviously mentioned supply chamber 19. Each of the top plates 16 has aninlet opening 21 (FIGS. 1 and 3) formed therein adjacent one end of theunderlying compartment 13a-13d and also adjacent the relatively low sideof plate 16 so that massecuite, magma or other material supplied to thechambers 19 and 20, as indicated by the flow lines 22 on FIG. 1, canpass from such supply chambers into the underlying compartments throughthe respective inlet openings.

Although the illustrated mingler has the chamber 19 supplying the samematerial to three underlying compartments 13a, 13b and 13c and thechamber supplying a different material to the single underlyingcompartment 13d, it will be apparent that the location and number of thepartitions extending to the top of tank 11 can be changed from thatshown to vary the number of compartments serviced by each of the supplychambers 19 and 20, and further that all of the partitions 14 and 15 maybe made to extend only up to the level of the plates 16, in which caseall of the compartments will receive material from the same supplychamber.

Each of compartments 13a-13d further has an outlet opening 23 adjacentthe bottom thereof and located near the end of the compartment remotefrom the inlet opening 21. Loading spouts, which are only generallyindicated at 24 on FIGS. 2 and 4 and may be arranged as shown in detailin US. Letters Patent No. 2,086,951, to Stevens, and No. 2,128,873, toRoberts, extend from the lower portion of tank 11 around the outletopenings 23 and are intended to deliver temperature conditionedmassecuite or magma from the several compartments of mingler 11 intorespective underlying centrifugal machines (not shown).

The rotary mingler coil unit 12 comprises a hollow shaft 25 extendinglongitudinally through the compartments 13a13d constituting the lowerportion of tank 11 and being freely rotatable in suitable openings inpartitions 14 and in a seal 26 provided in a suitable opening ofpartition 15. The hollow shaft 25 is of a strength sufficient to supportthe weight of rotary unit 12 between bearing assemblies 27 and 28located at the opposite ends of shaft 25 and carried by the end walls oftank 11. The bearing assembly 27 may be of the kind disclosed in detailin US. Letters Patent No. 3,009,683, to Grieselhuber, whereas referencemay be had to US. Letters Patent No. 2,654,364, to Hertrich, for asuitable arrangement of the bearing assembly 28.

The shaft 25 is surrounded throughout substantially its entire length bya concentric heat transferring-stirrer coil which is formed in sections29a, 29b, 29c and 29d disposed along the portions of the shaft containedin com partments 13a, 13b, 13c and 13d, respectively (FIG. 1). One endof the coil section 29a is connected with a chamber 30 (FIG. 6) formedin an end portion of shaft 25 between a partition 31 in the shaft andthe end Wall 32 of the latter adjacent bearing assembly 27. Chamber 30in turn is connected with a hollow extension 33 of shaft 25 which isrotatably supported in bearing assembly 27 and conducts hot Water orother heating fluid away from the mingler by way of a union 34 and anoiftake duct 35, as indicated schematically on FIG. 1 and which aredisclosed in greater detail in the previously referred to US. LettersPatent No. 3,009,683. The hot water or other heating fluid is suppliedto the mingler 11 through an intake duct 36 which, within the union 34,is connected to a tube 37 extending through shaft extension 33 andchamber 30 and opening into shaft 25 by way of an opening 38 in theshaft partition 31.

The end of coil section 29d near the adjacent end wall of housing 11 isconnected with the adjacent end of hollow shaft 25 and communicates withthe interior of the latter so that the heating fluid entering hollowshaft 25 through tube 37, at one end, travels along shaft 25 to theopposite end of the latter and there enters coil section 29a. Theadjacent ends of coil sections 29a and 29b, of coil sections 2911 and290, and of coil sections 29c and 29d are connected with each otherthrough transfer pipes 39 extending across the interior of hollow shaft25 in the regions of partitions 14 and 15, as shown on FIG. 5. Thus, theheating fluid, after having passed axially through hollow shaft 25, thenflows successively through the coil sections 29d, 290, 2911 and 2911before leaving the mingler through chamber 30, shaft extension 33, union34 and outtake duct 35.

The hollow shaft 25 is of sufiiciently large diameter to serve as aconduit for the heating fluid and also to contribute substantially tothe effective heating surface area provided by the assembly of the shaftand coil sections 29a-29d thereon. The coil sections 29a-29d have theirturns spaced apart in the axial direction and also radially from thesurface of shaft 25, as clearly shown on FIGS. 1, 4 and 5. Such spacingof the turns of the coil sections exposes the entire surface of eachcoil section for heat transferring contact with the material withintherelated compartment 13a-13d, and further makes it possible to inducelongitudinal movement of the material engaged by the coil section uponrotation of the latter with the shaft. As shown particularly on FIGS. 1and 2, rotation of shaft 25 and coil sections 29a29d may be effected byway of a sprocket 40 secured on shaft extension 33 and engaged by achain 41 running around a drive sprocket 42 on the shaft of a motor 43.

When the mingler is employed in connection with modern high capacitycentrifugal machines, the compartments 13a-13d must have correspondinglylarge volumes to accommodate sufiicient quantities of massecuite ormagma. It is desirable that the spacing between coil sections 29a-29dand the inner wall surfaces of compartments 13a-13d be relatively small,so that material in each compartment cannot move around the outside ofthe coil section in passing from inlet opening 21 to outlet opening 23.Thus, an increase in the cross-sectional size of each compartmentrequires a corresponding increase in the pitch diameter of the coilsection therein. Since an excessive increase in the diameter of hollowshaft 25 is unadvisable, in that it tends to reduce the capacity of thecompartment 13a-13d, an increase in the pitch diameter of the coilsections, as when designing a mingler for use with high capacitycentrifugal machines, results in a relatively large radial spacing ofthe turns of the coil sections from the outer surface of the centralhollow shaft.

It has been found that, during operation of a mingler having theconstruction described above, particularly one designed for use withhigh capacity centrifugal machines and hence having the coil sectionsspaced radially a relatively large distance from the surface of thehollow shaft, there is a tendency for the massecuite or magma to movelongitudinally through the space between each coil section 29a29d andshaft 25 as a more or less solid core and thereby reach the outletopening 23 of the related mingler compartment without coming intoadequate heat transferring and stirring contact with the coil section.In order to avoid the foregoing, the mingler 10 embodying this inventionhas impeller means, preferably in the form of paddle-like blades 44(FIGS. 4 and 5), welded or otherwise secured to hollow shaft 25 andextending radially into the space between the latter and the turns ofeach of coil sections 29a-29d. The outer ends of blades 44 preferablyterminate short of the turns of coil sections 29a-29d, and the blades onthe shaft in each compartment 13a-13d slope relative to the axis ofshaft 25 in the direction opposed to the slope of the turns of therelated coil section. Thus, when shaft 25 is rotated, as describedabove, blades 44 are operative to induce the material within the spacebetween shaft 25 and each coil section to move longitudinally in thedirection opposed to the movement of the material by that coil sectionand also radially outward toward the turns of the coil section.

As shown particularly on FIGS. 4 and 5, the blades 44 on shaft 25 withineach of compartments 13a-13d are spaced apart axially along the shaftand further are angularly spaced apart around the shaft, for example,with 120 angular spacings between successive blades. Further, as shownin FIG. 4, the grouping of the blades in one compartment, as indicatedin full lines at 44, is preferably staggered or angularly displaced by60 from the grouping or arrangement of blades in the next compartment,as indicated in broken lines at 44.

In the illustrated preferred embodiment of this invention, the severalcoil sections 29a-29d have their helices arranged so that, upon rotationof shaft 25, for example, in the clockwise direction as viewed on FIG.4, the turns of the coil sections induce longitudinal movement in eachof compartments 13a13d in the direction from the related inlet opening21 toward the outlet opening 23, that is, from left to right, as viewedon FIG. 1. On the other hand, paddle-like blades 44 are arranged sothat, upon such rotation of shaft 25, the material in each compartmentbetween shaft 25 and the related coil section is longitudinally movedfrom right to left, as viewed on FIG. 1, that is, in the direction awayfrom outlet opening 23, and also made to move radially outward towardthe turns of the related coil section. By reason of the presence ofblades 44, material within the space between shaft 25 and thesurrounding coil section cannot reach the outlet opening 23 withoutfirst coming into intimate and repeated heat transferring and stirringcontact with the turns of coil section 13a-13d.

It has been found that, by reason of the assurance of repeated intimateheat transferring and stirring contact of all the material within eachcompartment with the related coil section prior to discharge of suchmaterial to the associated centrifugal machine, relatively greatuniformity and accuracy is achieved in controlling the temperature ofthe massecuite or magma fed to the centrifugal. Although the drawings donot disclose the means by which the temperature of the dischargedmaterial may be controlled, reference may be had to the previouslymentioned U.S. Letters Patent No. 2,654,364, for a suitable arrangementfor affecting such control.

It has also been found that blades 44 tend to increase the relativevelocities of the material in each compartment with respect to the heattransferring surfaces of the coil section therein, therebycorrespondingly increasing the efficiency of such heat transfer. Thus,the improved efficiency of heat transfer to the massecuite or magmamakes it possible to reduce the temperature of the hot water or otherheating medium circulated through shaft 25 and oil sections 29a-29dthereon. Such reduction of the temperature of the heating medium isadvantageous in that it makes it possible to employ a temperature thatis as little as practicable in excess of the saturation temperature ofthe massecuite or magma. The fact that a mingler embodying thisinvention has improved heat transfer characteristics and further effectsmore uniform heating of the massecuite or magma in each of itscompartments makes it possible to relatively reduce the time duringwhich the material must remain in the mingler in order to reach thedesired temperature before being loaded into the associated centrifugalmachines. Thus, the mingler having the described constructional featuresis particularly adapted for use in connection with high capacitycentrifugal machines.

Although a particular embodiment of the invention has been described indetail herein with reference to the accompanying drawings, it is to benoted that the invention is not limited to that precise embodiment, andthat various changes and modifications may be effected therein by oneskilled in the art without departing from the scope or spirit of theinvention, except as defined in the appended claims.

What is claimed is:

l. In an apparatus for conditioning massecuite or like material, anelongated material receiving tank, a hollow rotatable shaft extendinglongitudinally in said tank, a

helical heat transferring-stirrer coil surrounding said shaft within thetank and being connected with the shaft for rotation of the coil withthe shaft, so that the material in the tank tends to be moved in onelongitudinal direction, and for a circulating flow of fluid through thecoil by way of the shaft, said helical coil having turns spaced fromsaid shaft so that heat transfer between the circulating fluid andmaterial in said tank occurs at the surface of said shaft and at theentire surface of said coil, and impeller blades extending radially fromsaid shaft into .the space between the latter and said turns of thecoil, said blades being spaced apart angularly and axially on said shaftand inclined relative to the axis of said shaft in the direction opposedto the inclination of said turns of the coil to urge the material withinsaid space in the other longitudinal direction and also radially outwardtoward the coil.

2. An apparatus for conditioning massecuite or like material accordingto claim 1; wherein said impeller blades have their radially outer endsspaced substantially from said turns of the coil.

3. In an apparatus for conditioning massecuite or like material, anelongated tank defining at least one compartment for containing thematerial during conditioning thereof and having an inlet and an outletfor the material spaced apart in the longitudinal direction of the tank,a hollow shaft rotatably mounted in said tank and extendinglongitudinally through said compartment, a helical heattransferring-stirrer coil surrounding said shaft within the compartmentand being connected with the shaft for rotation with the latter and fora circulating flow of fluid through the coil by way of the shaft, saidhelical coil having turns spaced from said shaft so that heat transferbetween the circulating fluid and material in said compartment occurs atthe surface of said shaft and at the entire surface of said coil, saidturns of the coil being adjacent the inner surface of said compartmentand sloping in one direction relative to the axis of the shaft to urgematerial in said compartment in the longitudinal direction from saidinlet toward said outlet in response to rotation of said shaft and coilin a predetermined direction, means operative to rotate said shaft insaid predetermined direction, and impeller means extending radially fromsaid shaft into the space between the latter and said turns of the coiland terminating short of said turns, said impeller means beingoperative, upon rotation of the shaft in said predetermined direction,to urge the material within said space in the longitudinal directionfrom said outlet toward said inlet and also radially outward toward saidturns of the coil, thereby to ensure that all material passing throughsaid compartment is uniformly subjected to the action of said heattransferringstirrer coil. 7

4. In an apparatus for conditioning massecuite or like material, anelongated tank defining at least one compartment for containing thematerial during conditioning thereof and having an inlet and an outletfor the material spaced apart in the longitudinal direction of the tank,a hollow shaft rotatably mounted in said tank and extendinglongitudinally through said compartment, a helical heattransferring-stirrer coil surrounding said shaft within the compartmentand being connected with the shaft for rotation with the latter and fora circulating flow of fluid through the coil by way of the shaft, saidhelical coil having turns spaced from said shaft so that heat transferbetween the circulating fluid and material in said compartment occurs atthe surface of said shaft and at the entire surface of said coil, saidturns of the coil being adjacent the inner surface of said compartmentand sloping in one direction relative to the axis of the shaft to urgematerial in said compartment in one longitudinal direction between saidinlet and outlet, and impeller blades extending radially from said shaftinto the space between the latter and said turns of the coil andterminating short of the latter so as to avoid interference with theheat transferring contact of the material with said entire surface ofthe coil, said blades sloping relative to the axis of the shaft in thedirection opposed to the turns of said coil so that, upon rotation ofthe shaft, said blades urge the material within said space in theopposite longitudinal direction and also radially outward toward saidturns of the coil, thereby ensuring that all material passing throughsaid compartment from said inlet to said outlet is uniformly subjectedto the action of said heat transferringstirrer coil.

5. An apparatus as in claim 4; wherein said inlet and outlet arerespectively located at the top and bottom of said compartment adjacentthe opposite ends of the latter; and

further comprising means rotating said shaft in the direction to causesaid turns of the coil to urge the material in said compartment in thelongitudinal direction from said inlet toward said outlet.

6. In a mingler for controlling the temperature of sugar massecuites,magmas or like material, an elongated tank having lateral partitioningmeans therein dividing the interior of the tank into upper and lowerportions and vertical partitioning means at least in said lower portionto divide the latter into a plurality of compartments, said lateralpartitioning means having an inlet opening therein for each of saidcompartments so that a supply of material maintained in said upperportion of the tank can enter said compartments through the relatedinlet openings, each inlet opening being disposed adjacent one end ofthe related compartment and the latter further having an outlet openingadjacent the opposite end thereof, a hollow shaft rotatably mounted insaid tank so as to extend longitudinally through said compartments, ahelical heat transferring-stirrer coil surrounding said shaft withineach of said compartments and being connected with the shaft forrotation with the latter and for a circulating flow of fluid through thecoil by way of said shaft, means for rotating said shaft, said helicalcoil in each compartment having turns spaced from said shaft and slopingin one direction relative to the axis of the shaft to urge material inthe related compartment to move longitudinally in the direction fromsaid inlet opening to said outlet opening, and impeller means extendingfrom said shaft into the space between the latter and said turns of thecoil in each compartment and being operative, upon rotation of theshaft, to urge the material within said space longitudinally in thedirection opposed to the movement thereof by the coil and also radiallyoutward toward the turns of the coil, thereby to ensure that allmaterial passing through each compartment is uniformly subjected to theaction of said heat transferringstirrer coil.

7. In a mingler for controlling the temperature of sugar massecuites,magmas or like material, an elongated tank having lateral partitioningmeans therein dividing the interior of the tank into upper and lowerportions and vertical partitioning means at least in said lower portionto divide the latter into a plurality of compartments, said lateralpartitioning means having an inlet opening therein for each of saidcompartments so that a supply of material maintained in said upperportion of the tank can enter said compartments through the relatedinlet openings, each inlet opening being disposed adjacent one end ofthe related compartment and the latter further having an outlet openingadjacent the opposite end thereof, a hollow shaft rotatably mounted insaid tank so as to extend longitudinally through said compartments, ahelical heat transferring-stirrer coil surrounding said shaft Withineach of said compartments and being connected with the shaft forrotation with the latter and for a circulating flow of fiuid through thecoil by way of said shaft, means for rotating said shaft, said helicalcoil in each compartment having turns spaced from said shaft and slopingin one direction relative to the axis of the shaft to urge material inthe related compartment to move longitudinally in the direction fromsaid inlet opening to said outlet opening, and impeller blades extendingradially from said shaft into the space between the latter and saidturns of the coil in each compartment, said blades sloping relative tothe axis of the shaft in the direction opposed to the turns of the coiland terminating short of the latter so that, upon rotation of the shaft,said blades urge the material within said space in the longitudinaldirection opposed to movement of the material by the coil and alsoradially outward toward the latter, thereby ensuring that all materialpassing through each compartment is uniformly subjected to the action ofsaid heat transferring-stirrer coil therein.

8. A mingler as in claim 7; wherein said lateral partitioning meansinclines downwardly toward one side of said tank and said inlet openingfor each compartment is disposed adjacent said one side of the tank.

References Cited by the Examiner UNITED STATES PATENTS 933,934 9/1909Valerius -92 2,160,533 5/1939 Bonath 127-16 2,540,250 2/1951 Feldsteinet al 12758 X 2,654,364 10/1953 Hertrich 127-17 FOREIGN PATENTS 397,4328/1933 Great Britain.

MORRIS O. WOLK, Primary Examiner.

MICHAEL E. ROGERS, Examiner.

1. IN AN APPARATUS FOR CONDITIONING MASSECUITE OR LIKE MATERIAL, ANELONGATED MATERIAL RECEIVING TANK, A HOLLOW ROTATABLE SHAFT EXTENDNGLONGITUDINALLY IN SAID TANK, A HELICAL HEAT TRANSFERRING-STIRRER COILSURROUNDING SAID SHAFT WITHIN THE TANK AND BEING CONNECTED WITH THESHAFT FOR ROTATION OF THE COIL WITH THE SHAFT, SO THAT THE MATERIAL INTHE TANK TENDS TO BE MOVED IN ONE LONGITUDINAL DIRECTION, AND FOR ACIRCULATING FLOW OF FLUID THROUGH THE COIL BY WAY OF THE SHAFT, SAIDHELICAL COIL HAVING TURNS SPACED FROM SAID SHAFT SO THAT HEAT TRANSFERBETWEEN THE CIRCULAING FLUID AND MATERIAL IN SAID TANK OCCURS AT THESURFACE